Objective To investigate the value of 18F-FDG PET/CT imaging in localization epileptogenic zone in presurgical evaluation of type I focal cortical dysplasia.Methods Preoperative 18F-FDG PET/CT imagings in 19 patients with epileptogenic type I focal cortical dysplasia confirmed by pathological results were retrospectively analyzed.The PET/CT images were qualitative visually assessed and quantitatively analyzed by NeuroQ software.All the results were compared with the pathology.Results The qualitative visually analysis found the FDG uptake decreased in single cerebral region of 12 patients, multiple cerebral regions in 7 patients.The qualitative analysis demonstrated FDG uptake decreased in multiple cerebral regions in 19 cases.The prominent regions of FDG uptake decreased were consistent with the pathological result.Conclusion The combination of PET-CT qualitative and quantitative analysis could increase the accuracy of epileptogenic focus localization in patients with type I focal cortical displasia.